function Fish(x,y,w,h,bgimg,count,time){
    var e = document.createElement("div");
    var s = e.style;
    s.position = "absolute";
    s.left = x;
    s.top = y;
    s.width = w;
    s.height = h/count;
    s.background = "url("+bgimg+")";
    document.body.appendChild(e);
    var bgy = 0;

    var timer = setInterval(function(){
        bgy = bgy - parseInt(s.height);
        if(bgy==-parseInt(s.height)*count/2) bgy = 0;
        s.background = "url("+bgimg+") 0px "+bgy+"px";
    },time);
}